we had a 1999 Minnie Winnie and it was a sweat box in the cab during the Texas Summers. Actually melted the lip stick in the YL's purse which was on the floor.
If you pull the engine cover you will see only a very thin heat shield and no insulation in the cab floor pan. Also, note the exhaust manifolds are within about 1/2 inch of the floor pan.
I spent part of a Saturday pulling the seats, engine cover and insulated the floor and inside the cover. Get the 3/8" foil backed fiber insulation from J.C. Whitney. Also get the foil tape to seal joins and the edges and the high temp spray adhesive to glue it in place. The bubble stuff sold by Camping World is junk and not meant for high temp duty.
It made the cab much cooler and also made it a bit quieter. Get two small rolls of the insulation and you will have enough left over for to line the generator compartment.
When fitting the floor, you may have to mes up the carpet as it may be glued down. I harassed Winnebago in to sending me the carpet to redo the cab floor. Cut the insulation back about 1" from the edge of the door sills and the engine cover so that *** will fit back like it is supposed to. Mark the holes for the 8 seat bolts so that it is easier to remount the seats. Took me about 5 hours to complete.
Amateur Radio Operator (KE5DFR)|Full-Time! - 2012 6.7L Ford Crew Cab Dually -2013 HitchHiker Champagne 38RLRSB - Travel with one Standard Schnauzer and one small Timneh African Gray Parrot